Original Articles
Correlation of sexual maturation with skeletal age of Southern Chinese girls
Lisa Y. So
Australian Orthodontic Journal 1997; 14(4):215-217
Quantification of ethnic differences in facial profile
Charles S. Sheridan, C. David L. Thomas, John G. Clement
Australian Orthodontic Journal 1997; 14(4):218-224
Dentofacial changes in patients with Class III malocclusions treated by a combination of activator and chin-cup appliances
Efthimia K. Basdra, Angelika Stellzig, Gerda Komposch
Australian Orthodontic Journal 1997; 14(4):225-228
Application of a case-based expert system to Orthodontic diagnosis and treatment planning
Roland M.S. Hammond, Terrence J. Freer
Australian Orthodontic Journal 1997; 14(4):229-233
The rotation of maxillary first molars, mandibular first molars, and maxillary first premolars in acceptable occlusions
G. Kristian Hansen, Joseph M. Caruso, Vic West, Craig A. Andreiko, James R. Farrage, M. Toufic Jeiroudi
Australian Orthodontic Journal 1997; 14(4):242-246
A new self-curing resin-modified glass-ioner cement for the direct bonding of Orthodontic brackets
John P. Fricker
Australian Orthodontic Journal 1997; 14(4):247-249
Case Report
Case Report: Non-extraction with functional and mechanical therapy of a Class II Division 1 malocclusion
Teruo Murakami, Naohiro Moro, Kiyoshi Abe
Australian Orthodontic Journal 1997; 14(4):235-241
Abstracts
Correlation of sexual maturation with skeletal age of Southern Chinese girls
Lisa L.Y. So
The correlation of skeletal maturation with the chronological ages of the onset of four secondary sexual characteristics (menarche, appearance of pubic hair and axillary hair, and breast development) was studied in a group of 117 Southern Chinese girls aged between 11 years, 9 months and 12 years, 3 months, who were born and brought up in Hong Kong. The skeletal maturation was assessed from left hand and wrist radiographs by the Greulich and Pyle Atlas Method (1959). The early maturers in sexual maturation were significantly more advanced in skeletal maturity with p<0.001.
Key words: Sexual characteristics, Skeletal age
Received for publication : September 1995
Accepted : July 1996
Aust Orthod J 1996; 14(4):215-217
Quantification of ethnic differences in facial profile
Charles S. Sheridan, C. David L. Thomas, John G. Clement
The concept of facial aesthetics is becoming increasingly important and with the expanding application of orthodontic, orthognathic, plastic and reconstructive techniques to patients from continually diversifying ethnic backgrounds, it is timely that more elaborate methods for the evaluation of facial form are adopted. The aim of the present study was to further investigate the use of Fourier shape analysis in the quantification of facial profile, and to investigate differences between racial groups. One hundred and twenty-two undergraduate dental students were photographed and surveyed for information pertaining to ethnic origin. Student’s t-tests revealed significant differences (p<0.05) in higher-order (fourth- and above) Fourier harmonics between male and female profiles, as well as between intervention and non-intervention groups. A comparison of multiple means test revealed significant differences (p<0.05) in the third-order Fourier harmonic (vertex projection) between the Asian group and three other groups - Angle-Celtic, Eastern European and Western European. Differences correlated with convexity in the lower third of the face, which was demonstrated by Fourier reconstruction.
Key words: Fourier, facial profile, ethnicity, racial
Received for publication : July 1996
Accepted : January 1997
Aust Orthod J 1996; 14(4):218-224
Dentofacial changes in patients with Class III malocclusions treated by a combination of activator and chin-cup appliances
Efthimia K. Basdra, Angelika Stellzig, Gerda Komposch
The purpose of this study was to examine, on pre-treatment and post-treatment lateral cephalograms, the effects of combined activator/chin-cup therapy on Class III patients, and to compare mean cephalometric differences noted during treatment with untreated Class I subjects. Fourteen females and fifteen males who exhibited a Class III malocclusion were the subjects of the study. Direct comparison of the mean value changes of the cephalometric variables during treatment of Class III patients with untreated Class I subjects revealed that SNA increased more and SNB increased less in the Class III patients than in the control group, thus improving the ANB angle. At the end of treatment, all patients had a positive overjet but a more concave profile. In this study, combined activator/chin-cup therapy seemed to induce improvement in those Class III patients selected for their moderate condition and treated over a five-year period. The changes seemed to indicate growth patterns which imitate those of the untreated Class I subjects. Moreover, dentoalveolar compensations helped to improve the overjet and conceal skeletal deviations.
Received for publication : September 1995
Accepted : July 1996
Aust Orthod J 1996; 14(4):225-228
Application of a case-based expert system to orthodontic diagnosis and treatment planning
Roland M.S. Hammond, Terrence J. Freer
Expert systems are being utilised increasingly in medical fields for the purposes of assisting diagnosis and treatment planning. A case-based system is a particular type of expert system that uses a store of previously treated cases to provide the knowledge for solving new problems. The aim of this study was to investigate the application of this methodology in the field of orthodontic diagnosis and treatment planning. Using a limited group of features, a case-base of 300 cases was entered into a case-based expert system shell. A test set of 30 consecutive cases was then used to test the diagnostic capacity of the system. The computer-generated treatment plan matched the actual treatment plan in 24 of the 30 cases. The system was also tested for its capacity to handle unusual cases. The system has useful potential.
Key words: Diagnosis, treatment planning, computers, expert systems
Received for publication : November 1995
Accepted : July 1996
Aust Orthod J 1996; 14(4):229-234
The rotation of maxillary first molars, mandibular first molars, and maxillary first premolars in acceptable occlusions
G. Kristian Hansen, Joseph M. Caruso, Vic West, Craig A. Andreiko, James R. Farrage, M. Toufic Jeiroudi
The rotation of the maxillary molars is considered important in the orthodontic treatment of malocclusions. In this study, a computer analysis program was developed to examine the rotations of maxillary molars, mandibular molars, and maxillary first premolars in casts of permanent dentitions with acceptable occlusions. Ninety-three sets of untreated ‘acceptable occlusion’ models from the collection of the Foundation for orthodontic Research (FOR) were scanned on a flat bed scanner. The images were analysed using custom software. Measurements were made by relating maxillary first permanent molars to the midline, archform, opposite canine, and mandibular first permanent molars. The mandibular first molars and maxillary first premolars were also analysed and their rotations measured. The mean rotations of the maxillary first molars, measured as the angle between a line joining the tips of the buccal cusps and a line tangent to the appropriate archwire form (from Ricketts’ Pentamorphic Arches) at the first molars, were 0.59 and -0.72 degrees (positive values represent mesio-lingual rotations) for the right and left, respectively. For the mandibular molars, these means were 6.34 and 8.40 degrees, respectively. The mean differences in rotation between buccal cusp tips of maxillary and mandibular first molars in occlusion were 5.75 and 9.12 degrees for the right and left, respectively, with the mandibular being more mesio-lingually rotated. The differences between left and right were significant for all measurements. The present study brings into question the suitability of our present ‘straight wire’ prescriptions in producing similar occlusions. It also suggests that scanning models for computer analysis may be a be a practical and precise way to measure similar rotations in untreated normal and treated occlusions.
Received for publication : November 1995
Accepted : August 1996
Aust Orthod J 1996; 14(4):242-246
A new self-curing resin-modified glass-ionomer cement for the direct bonding of Orthodontic brackets
John P. Fricker
A new self-curing (chemically-cured), resin-modified glass-ionomer cement, Fuji Ortho (GC International Japan) is based on the technology of hydrid glass-ionomer restorative materials and features chemical adhesion to tooth structure, and long-term fluoride release. These materials do not require acid etching of the tooth for adhesion, thereby preserving the integrity of the enamel prisms. This paper describes the clinical use of Fuji Ortho for the direct bonding of orthodontic (metal) brackets.
Key words : Bonding, resin-modified glass-ionomer cements
Received for publication : October 1996
Accepted : December 1996
Aust Orthod J 1996; 14(4):247-249
Case report: Non-extraction treatment with functional and mechanical therapy of a Class II division 1 malocclusion
Teruo Murakami, Naohiro Moro, Kiyoshi Abe
Non extraction treatment was carried out for a growing Angle Class II division 1 patient. Because the patient demonstrated potential growth and all the third molars were congenitally missing, the extraction of the four premolars was ruled out.
A functional appliance (MGA) and cervical headgear were employed simultaneously in the first phase of treatment. The second phase was carried out by mechanotherapy. As a result, adequate forward growth of the mandible was attained and all 28 teeth were kept in good relation with no root resorption and healthy periodontal tissue. A better improvement of the profile may have been attained had extraction treatment been performed; with non-extraction treatment, however, the amount of tooth movement could be minimized, and root resorption was not observed. The role of the functional appliance is also important for the success of non-extraction treatment in Class II patients.
Key words: Non-extraction treatment, Class II malocclusion, functional and mechanical therapy .
Received for publication : February 1996
Accepted : August 1996
Aust Orthod J 1996; 14(4):235-241